Pole-changer transmitter



Jan. 14, 1930. J. w. SNYDER POLECHANGER TRANSMITTER Filed Oct. 12. 1927 Patented Jan. 14, 1935) 1 7 3 UNITED STATES PATENT ()FFICE JOSEPH W. SNYDER, F FARGO, NORTH DAKOTA POLE-CHANGER TRANSMITTER Application filed October 12, 1927. Serial No. 225,755.

This invention relates to a polechanger duplex, quadruplex and multiplex telegraph transmitter wherein a permanent magnet is and telephone circuits. employed and upon one of its poles, usually The polechanger transmitter A is prothe lower one, is fastened a U-shaped elecvided with a permanent magnet 1, one end tromagnet. This magnet may be wound to of which is connected with a cross bar 3. 55 any number of ampere turns desired to meet This cross bar connects the electromagnet local conditions. coils 2 which are wound to any resistance A feature of the invention resides in so desired and ampere turns necessary to acconstructing the electrically excited magnet tuate it in any circuit.

to provide two separate pole pieces, individ- The other end of the permanentmagnet 63 ually adjustable by which the bias CODCllis adapted to be connected with adjustable tion is accomplished, between these two pole pole pieces 4 and 5, between which the polarpieces. The lower end of the armature, beized lower end of the armature 6 plays low the pivot points, is caused to move to freely.

and fro, as induced by the electromagnetism The armature 6 is pivoted in the slot '7 in the U-shaped electromagnet. formed in the upper end of the permanent It is also a feature of my invention to promagnet l and a yoke 8 having depending vide a small iron drum between the pivot side ears 9 which curve inwardly extends points of the armature, the purpose ofwhich from the divided end of the permanent magis to avoid loss of magnetic flux. net and in a manner so as to support adjust- 7c The electrically excited magnet is actuated ing screws i0 by the ears 9. by local current. \Vhen the local current is The armature 6is pivoted in the slot? of the released the armature swings back to its norupper end of the permanent magnet 1 and mal stop being attracted by the biased mag is held by the pivot member 12 which is netic adjustment avoiding the recoil from pointed on its ends and which is adapted 75 the use of retractile tensionsprings which to be adjusted by the screw 13. I provide have been used heretofore, also overcoming a cylindrical small iron member 14 around the arcing which is detrimental to a proper the pivot member 12, the purpose of which. functioning of the apparatus at th distant is to avoid loss of magnetic flux. The upper end. end 15 of the armature 6 tapers toward a so My polechanger transmitter provides a point and is adapted to carry the contact construction giving economy on the silver points 16 on either side thereof. and platinum points by reducing the arc. Bracket arms 17 are provided extending This is an important feature of the inven-' upwardly from the upper end of the pertion. My polechanger is adapted to telemanent magnet and attached thereto but 85 graph transmission, and also in telephone separated by insulation 18. These bracket circuits where a device of this nature is do arms 17 carry a pair of adjusting screws 19 sirable. which have contact points 20. The contact These features, together with other depoints 20 are adapted to be adjusted in retails and objects of my invention will be lation to the contact points 16 on the arma- 90 more fully and clearly set forth in the speciture 6 to adjust the armature 6 in its operafication and claims. tion.

In the drawings forming part of this To actuate the armature by energizing the specification: coils 2 of the electromagnet B, it should be Figure 1 is a side view of my polechanger biased, which is accomplished by adjusting 95 transmitter. the pole pieces 4 closer to the depending por- Figure 2 is a front view of the polechanger tion 22 of the armature 6, which extends betransmitter. tween the pole pieces 4 and 5, than it is posi- The drawings illustrate my polechanger tioned to the pole piece 5. This is for the transmitter A which is adapted for single, purpose of producing the desired signals. 100

the armature It is evident that either of the pole pieces a or 5 may be adjusted as just described in closer relation to the end 22 of the armature 6, one to the other, or in other words, one of the pole pieces a or 5 must be closer to the end 22 than the other to set my polechanger transmitter biased, and this is necessary to produce the desired signals.

The electromagnet, consisting of the coils 2 which are energized or excited by the local current, has very soft iron cores and is wound to any resistance desired to give the ampere turns necessary to actuate it on any circuit.

The adjusting screws 19 which are marked plus and minus are to be connected in the main line source of current, while the armature is connected with the line on which the transmission operates. By means of a small wire connection 24 the armature is connected to the yoke 8 to insure good contact at all times.

The principles of operation of my polechanger transmitter A are the biased armature 6 playing freely between the two electromagnetic pole pieces 4 and 5, while the permanent magnet induces magnetic force to The unlike poles attract, while like poles repel. This pole changer transmitter is particularly adapted for use in telegraph transmission of signals and may be for single, duplex, quadruplex and multiplex telegraph and also for telephone circuits where an electrical signal is transmitted. The features of advantage which are of primary importance in my polechanger include a means of providing polechanger transmitter wherein the recoil obtained from using retractile tension springs is avoided and in a delicate instrument. of this nature this is highly important. I also accomplish with my polechanger a mini mizing of the yoke on the silver and platinum points which permits the changer to function more readily and economizes in the use of the same. The simple, inexpensive structure in my polechanger transmitter I have found to be very practical in actual use and the same accomplishes results which from my knowledge of telegraphy are very Y desirable.

In accordance with the patent statutes I have described the principles of my polechanger transmitter and while I have illustrated the construction in particular formation and nature I desire to have it understood that the same is only illustrative of a means of carrying out my invention and that changes and variations may be made within the scope of the following claims without departing from the spirit of my invention. I

I claim:

1. A polechanger transmitter comprising, a U-shaped permanent magnet, an electro-.

magnet attached to one end of said perma- 7 nent magnet, independently adjustable pole pieces for said electromagnet, an armature pivotally secured to the other end of said permanent magnet, adjustable contact screws for one end of said armature adapted to connect the same with the main line, a yoke supported from the end of said permanent magnet carrying said armature, said yoke being provided with means for supporting adjusting screws for said pole pieces of said electrom'agnet.

2. A polechanger including, a permanent magnet, an electromagnet supported on one end of said permanent magnet, adjustable pole pieces for said electromagnet, an armature pivotally supported by the other end of said permanent magnet, a yoke extending from the end of said permanent magnet supporting said armature, adjusting screws carried by said yoke for said pole pieces of said electromagnet, and contact points adjustably positioned on either side of said armature to connect the same with the main line.

3. A polechanger transmitter including a permanent magnet, an. electromagnet supported on one end of said permanent magnet pole pieces therefore, the other end of said permanent magnet being bifurcated to receive an armature, means for pivotally supporting the armature by said bifurcated end, and a plurality of independently operable adjusting means extending from said armature supporting means andoperatively connected to said pole pieces, whereby the latter may be adjusted with respect to the armature.

JOSEPH w. snrnnn." 

